An integrated circuit (IC) packaging system electrically couples an IC die to various external elements, and may also provide thermal and physical protection to the IC die. In order to increase processing power and/or functionality within a given footprint, an IC packaging system may support two or more IC die. For example, a “stacked die” IC packaging system may include an IC package with two or more IC die stacked thereon. According to another example, a “stacked package” IC packaging system may include several IC packages stacked on one another, with each IC package having one or more IC die stacked thereon, and with adjacent IC packages being separated by a solid polymer interposer including conductive plugs for electrically coupling the adjacent IC packages.
The foregoing IC packaging systems may present characteristics that may be undesirable in certain scenarios. These characteristics may include: limits on the relative sizes of adjacent IC die; wire bonding congestion on one or more IC packages; long wirebonds; inefficient fabrication processes; and/or limited ability to test IC die prior to final packaging.